It is known that the surfaces of organs after being damaged during surgery are conjugated to surrounding tissues, and thus postoperative adhesions occur. The postoperative adhesions cause, for example, infertility due to fallopian tube adhesions, intestinal obstruction due to intestinal adhesions, and the like, and require a second surgery, which imposes a heavy burden on patients. Furthermore, the second surgery may even cause additional damage to the organs as a result of dissection of the adhesion site. In order to prevent such postoperative adhesions, an antiadhesive material in film form is known with which a wound site is physically covered on the surgery.
Meanwhile, the cases of endoscopic surgery has recently been increasing because of the small wounds and the relatively short-term hospitalization.
However, in such endoscopic surgery, the use of a conventional antiadhesive material in film form is often difficult. When using an antiadhesive material in film form in endoscopic surgery, it is necessary to roll up the film to a size equal to or smaller than the inner diameter of a trocar, insert the film into the body, open the film in the body, and place the film on an affected part. Thus, the operations are complicated. Therefore, there are cases where the film may be broken, or where the film cannot be correctly placed on the affected part.
In contrast, for example, new antiadhesive materials containing crosslinked poly-γ-glutamic acid as the main ingredient have been developed that can be processed into powder or gel form and are thus easy to handle, see: WO 2006/054624 and WO 2007/132785. However, there are still problems in manufacturing, such as the control of the degree of crosslinking, with these antiadhesive materials.
The present invention has been made to solve the above-described problems, and it is an object thereof to provide an antiadhesive material that is easy to handle even when applied to a case such as endoscopic surgery and that can effectively prevent postoperative adhesion of organs in a wound site.